Electro-optical device and electronic apparatus

ABSTRACT

In an electro-optical device, in an interlayer insulating layer provided in a layer between a transistor and a scanning line, a first opening and a second opening are respectively provided on both sides of a semiconductor layer in plan view, and a portion of a gate electrode is provided inside each of the first opening and the second opening. Therefore, the gate electrode configures a light shielding wall inside each of the first opening and the second opening. Of the first opening and the second opening, the first opening is provided at a position overlapping with the scanning line in plan view, and the gate electrode is electrically connected to the scanning line via the first opening. The second opening is provided at a position that does not overlap with the scanning line in plan view. Thus, the width of the scanning line can be made narrower.

The present application is based on, and claims priority from JPApplication Serial Number 2020-013343, filed Jan. 30, 2020, thedisclosure of which is hereby incorporated by reference herein in itsentirety.

BACKGROUND 1. Technical Field

The present disclosure relates to an electro-optical device including atransistor in which a gate electrode is provided on the opposite sidefrom a scanning line with respect to a semiconductor layer, and anelectronic apparatus.

2. Related Art

An electro-optical device (a liquid crystal device) used as a lightvalve or the like of a projection-type display apparatus is providedwith a semiconductor layer between a substrate main body and a pixelelectrode, and a transistor is configured using the semiconductor layer.In such an electro-optical device, when light from a light source isincident on an LDD region, which is interposed between a pixelelectrode-side source drain region electrically coupled to a pixelelectrode side of the semiconductor layer, and a channel region, thiscauses an optical leakage current to be generated in the transistor.Thus, a structure is conceivable in which a semiconductor layerextending along a scanning line is provided so as to overlap with thescanning line, a gate electrode is provided on the opposite side fromthe scanning line with respect to the semiconductor layer, and the gateelectrode and the scanning line are electrically coupled via an openingprovided in both sides of the semiconductor layer (see FIG. 2B and thelike of WO 2017/086116). According to such a structure, incidence oflight on the LDD region can be suppressed by the gate electrode providedinside the opening.

However, in order to electrically couple the gate electrode with thescanning line via the opening provided in both sides of thesemiconductor layer, and also to suppress the incidence of light on thesemiconductor layer using the gate electrode provided inside theopening, it is necessary to form the scanning line such that the widthof the scanning line overlaps with the opening provided in both sides ofthe semiconductor layer. Therefore, when light shielding is performed bythe gate electrode inside the opening provided in both sides of thesemiconductor layer, the width of the scanning line needs to be widened,and thus, a problem arises in that a reduction in a pixel aperture ratiocannot be avoided.

SUMMARY

In order to solve the problem describes above, an electro-optical deviceaccording to an aspect of the present disclosure includes a scanningline; a transistor including a semiconductor layer extending in anoverlapping manner with the scanning line in plan view and a gateelectrode having light shielding properties and disposed on a side,opposite from the scanning line, of the semiconductor layer, and aninterlayer insulating layer in a layer between the transistor and thescanning line, the interlayer insulating layer including a first openingand a second opening provided with the semiconductor layer interposedtherebetween in plan view, a portion of the gate electrode beingprovided inside each of the first opening and the second opening. Thefirst opening is provided at a position overlapping with the scanningline in plan view, and the second opening is provided at a position notoverlapping with the scanning line in plan view.

The electro-optical device according to the present disclosure is usedfor various electronic apparatuses. According to an aspect of thepresent disclosure, when the electronic apparatus is a projection-typedisplay apparatus, the projection-type display apparatus is providedwith a light source unit that emits a light to be supplied to theelectro-optical device, and a projection optical system that projectsthe light modulated by the electro-optical device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an electro-optical device according to a firstexemplary embodiment of the present disclosure.

FIG. 2 is a cross-sectional view of the electro-optical deviceillustrated in FIG. 1.

FIG. 3 is a plan view of a plurality of pixels adjacent to each other inthe electro-optical device illustrated in FIG. 1.

FIG. 4 is an enlarged plan view illustrating one of the pixelsillustrated in FIG. 3.

FIG. 5 is a cross-sectional view taken along a line A-A′ illustrated inFIG. 4.

FIG. 6 is a cross-sectional view taken along a line B-B′ illustrated inFIG. 4.

FIG. 7 is a plan view of a scanning line, a semiconductor layer, a gateelectrode, and the like illustrated in FIG. 5 and FIG. 6.

FIG. 8 is a plan view of a first capacitance electrode, a secondcapacitance electrode, and the like illustrated in FIG. 5 and FIG. 6.

FIG. 9 is a plan view of a data line, a capacitance line, and the likeillustrated in FIG. 5 and FIG. 6.

FIG. 10 is an enlarged plan view of the periphery of a first opening anda second opening illustrated in FIG. 7.

FIG. 11 is a cross-sectional view taken along a line C-C′ illustrated inFIG. 10.

FIG. 12 is an explanatory diagram illustrating a method formanufacturing the electro-optical device illustrated in FIG. 1.

FIG. 13 is an explanatory diagram illustrating the electro-opticaldevice according to a second exemplary embodiment of the presentdisclosure.

FIG. 14 is an explanatory diagram illustrating the electro-opticaldevice according to a third exemplary embodiment of the presentdisclosure.

FIG. 15 is a schematic configuration view of a projection-type displayapparatus using the electro-optical device to which the presentdisclosure is applied.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments of the disclosure will be described below withreference to the drawings. Note that, in each of the figures to bereferred to in the following description, to illustrate each layer, eachmember, and the like in a recognizable size in the drawings, each layer,each member, and the like are illustrated at a different scale. Further,in the following description, when each of layers formed in a firstsubstrate 10 is described, an upper layer side or a front surface sidemeans an opposite side (a side on which a second substrate 20 islocated) to a side on which a substrate main body 19 is located, and abottom layer side means the side on which the substrate main body 19 islocated. Further, of two directions intersecting each other in anin-plane direction of the first substrate 10, a direction in which adata line 6 a extends is referred to as a first direction Y, and adirection in which a scanning line 3 a extends is referred to as asecond direction X. Further, one side in the direction along the firstdirection Y is a first side Yl in the first direction Y, the other sidein the direction along the first direction Y is a second side Y2 in thefirst direction Y, one side in the direction along the second directionX is a first side X1 in the second direction X, and the other side inthe direction along the second direction X is a second side X2 in thesecond direction X.

First Exemplary Embodiment 1. Configuration of Electro-optical Device100

FIG. 1 is a plan view of an electro-optical device 100 according to afirst exemplary embodiment of the present disclosure. FIG. 2 is across-sectional view illustrating the electro-optical device 100illustrated in FIG. 1. As illustrated in FIG. 1 and FIG. 2, in theelectro-optical device 100, a first substrate 10 and a second substrate20 are bonded together by a seal material 107 with a predetermined gaptherebetween, and the first substrate 10 and the second substrate 20face each other. The seal material 107 is provided in a frame shape soas to follow an outer edge of the second substrate 20, and anelectro-optical layer 80 such as a liquid crystal layer is provided in aregion surrounded by the seal material 107, between the first substrate10 and the second substrate 20. The seal material 107 is a photocurableadhesive, or a photocurable and thermosetting adhesive, and a gapmaterial, such as glass fiber or glass beads, for setting a distancebetween the substrates to a predetermined value, is mixed in the sealmaterial 107. In the present exemplary embodiment, both the firstsubstrate 10 and the second substrate 20 have a quadrangular shape, andin a substantially central portion of the electro-optical panel 100, adisplay region 10 a is provided as a quadrangular region. In accordancewith such a shape, the seal material 107 is also provided in asubstantially quadrangular shape, and a peripheral region 10 b having arectangular frame shape is provided between an inner peripheral edge ofthe seal material 107 and an outer peripheral edge of the display region10 a.

The first substrate 10 includes a substrate main body 19 formed by alight-transmitting substrate, such as a quartz substrate, a glasssubstrate, or the like. On a first surface 19 s side, which is thesecond substrate 20 side of the substrate main body 19, outside thedisplay region 10 a, a data line driving circuit 101 and a plurality ofterminals 102 are formed along one side of the first substrate 10, andscanning line driving circuits 104 are formed along other sides adjacentto the one side. Although not illustrated, a flexible wiring substrateis coupled to the terminals 102, and various potentials and varioussignals are input to the first substrate 10 via the flexible wiringsubstrate.

On the first surface 19 s side of the substrate main body 19, in thedisplay region 10 a, a plurality of pixel electrodes 9 a, which aretransmissive and formed of an indium tin oxide (ITO) film and the like,are formed in a matrix pattern. A first oriented film 16 is formed onthe second substrate 20 side with respect to the pixel electrodes 9 a,and the pixel electrodes 9 a are covered with the first oriented film16.

The second substrate 20 includes a substrate main body 29 formed by atransmissive substrate, such as a quartz substrate, a glass substrate,or the like. On the substrate main body 29, a transmissive commonelectrode 21, which is formed of the ITO film and the like, is formed onthe side of a first surface 29 s that faces the first substrate 10, anda second oriented film 26 is formed on the first substrate 10 side withrespect to the common electrode 21. The common electrode 21 is formedover substantially the entire surface of the second substrate 20, and iscovered with the second oriented film 26. On the second substrate 20, alight shielding layer 27, which has light shielding properties and isformed by a resin, a metal, or a metal compound, is formed between thesubstrate main body 29 and the common electrode 21, and a transmissiveprotective layer 28 is formed between the light shielding layer 27 andthe common electrode 21. The light shielding layer 27 is formed, forexample, as a partition 27 a having a frame-like shape extending alongthe outer peripheral edge of the display region 10 a. The lightshielding layer 27 is also formed as a light shielding layer 27 b thatconfigures a black matrix in regions overlapping in plan view withregions respectively interposed between the pixel electrodes 9 aadjacent to each other. Dummy pixel electrodes 9 b, which are formedsimultaneously with the pixel electrodes 9 a, are formed in regions ofthe peripheral region 10 b of the first substrate 10 that overlap withthe partition 27 a in plan view. Note that a lens may be provided on thesecond substrate 20 at a position facing the pixel electrodes 9 a, andin this case, the light shielding layer 27 b is not often formed.

The first oriented film 16 and the second oriented film 26 are each, forexample, an inorganic oriented film formed by a diagonallyvapor-deposited film of SiO_(x) (x<2), SiO₂, TiO₂, MgO, Al₂O₃, or thelike, and liquid crystal molecules having negative dielectric anisotropyused for the electro-optical layer 80 are diagonally oriented.Therefore, the liquid crystal molecules form a predetermined angle withrespect to the first substrate 10 and the second substrate 20. In thisway, the electro-optical device 100 is configured as a verticalalignment (VA) mode liquid crystal device.

On the first substrate 10, inter-substrate conduction electrodes 109 forestablishing electrical conduction between the first substrate 10 andthe second substrate 20 are formed in regions located outside the sealmaterial 107 and overlapping with corner portions of the secondsubstrate 20. An inter-substrate conduction material 109 a includingconductive particles is disposed in the inter-substrate conductionelectrode 109, and the common electrode 21 of the second substrate 20 iselectrically coupled to the first substrate 10 side via theinter-substrate conduction material 109 a and the inter-substrateconduction electrode 109. Thus, a common potential is applied to thecommon electrode 21 from the first substrate 10 side.

In the electro-optical device 100, the pixel electrodes 9 a and thecommon electrode 21 are formed of a transmissive conductive film such asthe ITO film, and the electro-optical device 100 is configured as atransmissive liquid crystal device. In the electro-optical device 100,light that is incident on the electro-optical layer 80 from one of thefirst substrate 10 and the second substrate 20 is modulated whilepassing through the other substrate and being emitted, and displays animage. In the present exemplary embodiment, as indicated by an arrow L,light incident from the second substrate 20 is modulated by theelectro-optical layer 80 for each pixel while passing through the firstsubstrate 10 and being emitted, and displays an image.

2. Schematic Configuration of Pixels

FIG. 3 is a plan view of a plurality of pixels adjacent to each other inthe electro-optical device 100 illustrated in FIG. 1. FIG. 4 is anenlarged plan view illustrating one of the pixels illustrated in FIG. 3,and an enlarged view around the transistor 30 is illustrated in FIG. 4.FIG. 5 is a cross-sectional view taken along a line A-A′ illustrated inFIG.4. FIG. 6 is a cross-sectional view taken along a line B-B′illustrated in FIG. 4. Note that, in FIG. 3 and FIG. 4, and FIG. 7 toFIG. 9 to be described later, each of the layers are respectivelyindicated by lines described below. Further, in FIG. 3 and FIG. 4, andFIG. 7 to FIG. 9 to be described later, for the layers whose endportions overlap with each other in plan view, positions of the endportions are shifted to make the shape and the like of the layers easilyrecognizable. Further, a first opening 41 a and a second opening 41 bare illustrated by gray regions.

The scanning line 3 a is indicated by a thick solid line

A semiconductor layer 1 a is indicated by a thin broken line of shortdashes.

A gate electrode 8 a is indicated by a thin solid line.

A first capacitance electrode 4 a is indicated by a thin broken line oflong dashes.

A second capacitance electrode 5 a is indicated by a thin one-dot chainline.

The data line 6 a and relay electrodes 6 b and 6 c are indicated bythick broken lines of long dashes.

A capacitance line 7 a and a relay electrode 7 b are indicated by thicktwo-dot chain lines.

The pixel electrodes 9 a are indicated by thick broken lines of shortdashes.

As illustrated in FIG. 3 and FIG. 4, the pixel electrode 9 a is formedin each of the plurality of pixels on a surface of the first substrate10 facing the second substrate 20, and the scanning line 3 a, the dataline 6 a, and the capacitance line 7 a extend along an inter-pixelregion interposed between the pixel electrodes 9 a adjacent to eachother. The data line 6 a extends in the first direction Y in theinter-pixel region, and the scanning line 3 a extends in the seconddirection X in the inter-pixel region. The capacitance line 7 a extendsin the first direction Y and the second direction X in the inter-pixelregion. Further, the transistor 30 is formed corresponding to anintersection between the data line 6 a and the scanning line 3 a. Here,the scanning line 3 a, the data line 6 a, and the capacitance line 7 ahave light shielding properties. Therefore, a region in which thescanning lines 3 a, the data lines 6 a, the capacitance lines 7 a, andelectrodes provided in the same layer as those wiring lines are formedis a light shielding region 12 through which light is not transmitted,and regions surrounded by the light shielding region 12 are apertureregions 11 through which light is transmitted.

As illustrated in FIG. 5 and FIG. 6, in the first substrate 10,interlayer insulating layers 41, 42, 43, 44, and 45 are sequentiallylayered in this order from the substrate main body 19 side, between thesubstrate main body 19 and the pixel electrodes 9 a. Each of theinterlayer insulating layers 41, 42, 43, 44, and 45 is formed of atransmissive insulating film such as silicon oxide. In the presentexemplary embodiment, surfaces, on the pixel electrode 9 a side, of theinterlayer insulating layers 43, 44, and 45 are each formed as acontinuous flat surface by chemical machine polishing or the like. Inthe present exemplary embodiment, various wiring lines to be describedbelow and the transistor 30 are provided using a space between theinterlayer insulating layer and the substrate main body 19, and spacesbetween the interlayer insulating layers.

3. Detailed Description of each Layer

A detailed configuration of the first substrate 10 will be describedwith reference to FIG. 5 and FIG. 6, while referring as necessary toFIG. 7 to FIG. 9 to be described below. FIG. 7 is a plan view of thescanning line 3 a, the semiconductor layer 1 a, the gate electrode 8 a,and the like illustrated in FIG. 5 and FIG. 6. FIG. 8 is a plan view ofthe first capacitance electrode 4 a, the second capacitance electrode 5a, and the like illustrated in FIG. 5 and FIG. 6. FIG. 9 is a plan viewof the data line 6 a, the capacitance line 7 a, and the like illustratedin FIG. 5 and FIG. 6. Note that, in FIG. 7 to FIG. 9, contact holesrelating to electrical coupling of electrodes and the like illustratedin those figures are illustrated, and at the same time, thesemiconductor layer 1 a and the pixel electrodes 9 a are illustrated forthe purpose of indicating reference positions.

First, as illustrated in FIG. 5 and FIG. 6, in the first substrate 10,the scanning line 3 a extending along the second direction X is formedbetween the substrate main body 19 and the interlayer insulating layer41. The scanning line 3 a is formed of a conductive film having lightshielding properties such as a metal silicide film, a metal film, ametal compound film, or the like. In the present exemplary embodiment,the scanning line 3 a is formed from tungsten silicide (WSi), tungsten,titanium nitride, or the like. The transistor 30 for pixel switching isconfigured between the interlayer insulating layer 41 and the interlayerinsulating layer 42. The transistor 30 includes the semiconductor layer1 a formed on the surface of the interlayer insulating layer 41 on theopposite side from the substrate main body 19, a gate insulating layer 2layered on the pixel electrode 9 a side of the semiconductor layer 1 a,and the gate electrode 8 a overlapping with the semiconductor layer 1 aon the pixel electrode 9 a side of the gate insulating layer 2 in planview. The semiconductor layer 1 a is formed of a polysilicon film or thelike. The gate insulating layer 2 has a two-layer structure configuredby a first gate insulating layer 2 a that is formed of a silicon oxidefilm obtained by thermally oxidizing the semiconductor layer 1 a, and asecond gate insulating layer 2 b that is formed of a silicon oxide filmformed, for example, by a low pressure CVD method. The gate electrode 8a is formed of a conductive film such as a conductive polysilicon film,a metal silicide film, a metal film, or a metal compound film.

The interlayer insulating layer 41 provided between the scanning line 3a and the transistor 30 is provided with the first opening 41 a and thesecond opening 41 b such that the first opening 41 a and the secondopening 41 b are positioned on either side of the semiconductor layer 1a in plan view, and the first opening 41 a is provided as a contact hole41 g that electrically couples the scanning line 3 a with the transistor30. A detailed configuration of the first opening 41 a and the secondopening 41 b will be described below with reference to FIG. 10 to FIG.12.

As illustrated in FIG. 7, the scanning line 3 a includes a wiringportion 3 a 0 extending linearly along the second direction X, andprotruding portions 3 a 1 and 3 a 2 that protrude from the wiringportion 3 a 0 so as to overlap with the data line 6 a on both the firstside Y1 and the second side Y2 in the first direction Y. Further, thewiring portion 3 a 0 is provided with a protruding portion 3 a 3 thatprotrudes from the wiring portion 3 a 0 to the first side Y1 in thefirst direction Y.

The semiconductor layer 1 a extends from an intersecting section of thescanning line 3 a and the data line 6 a to the second side X2 in thesecond direction X so as to overlap with the scanning line 3 a in planview, and a portion overlapping with the gate electrode 8 a in plan viewis a channel region 1 c. In the present exemplary embodiment, thetransistor 30 has a lightly doped drain (LDD) structure. Therefore, onthe semiconductor layer 1 a, a first region is provided on the firstside X1 in the second direction X with respect to the channel region 1c, on which the data line 6 a is located, includes a data line-sidesource drain region 1 t separated from the channel region 1 c, and adata line-side LDD region lu interposed between the data line-sidesource drain region 1 t and the channel region 1 c. The data line-sideLDD region 1 u has a lower impurity concentration than the dataline-side source drain region 1 t. Further, on the semiconductor layer 1a, a second region 1 d provided on the second side X2 in the seconddirection X with respect to the channel region 1 c, which is theopposite side from the data line 6 a, includes a pixel electrode-sidesource drain region le separated from the channel region 1 c, and apixel electrode-side LDD region if interposed between the pixelelectrode-side source drain region le and the channel region 1 c. Thepixel electrode-side LDD region if has a lower impurity concentrationthan the pixel electrode-side source drain region 1 e.

The gate electrode 8 a includes a first electrode portion 8 a 0extending in the first direction Y so as to overlap with thesemiconductor layer 1 a in plan view with the gate insulating layer 2interposed therebetween, and second electrode portions 8 a 1 and 8 a 2extending in the second direction X along the semiconductor layer 1 afrom both end portions, in the first direction Y, of the first electrodeportion 8 a 0 on both sides of the semiconductor layer 1 a in the firstdirection Y. The second electrode portions 8 a 1 and 8 a 2 do notoverlap with the semiconductor layer 1 a in plan view.

Returning to FIG. 5 and FIG. 6 again, the interlayer insulating layers42 and 43 are formed on the upper layer side of the transistor 30.Between the interlayer insulating layer 42 and the interlayer insulatinglayer 43, a capacitance element 55 is provided that includes the firstcapacitance electrode 4 a, a dielectric layer 40, and the secondcapacitance electrode 5 a. The capacitance element 55 is a retentioncapacitor that prevents fluctuations in image signals retained by aliquid crystal capacitor, which is configured between the pixelelectrode 9 a of the first substrate 10 and the common electrode 21 ofthe second substrate 20. The first capacitance electrode 4 a and thesecond capacitance electrode 5 a are each formed of a conductive filmhaving light shielding properties such as a metal silicide film, a metalfilm, a metal compound film, or the like.

As illustrated in FIG. 8, the first capacitance electrode 4 a includes amain body portion 4 a 1 extending in the second direction X so as tooverlap with the scanning line 3 a and the semiconductor layer 1 a inplan view, and a protruding portion 4 a 2 protruding from the main bodyportion 4 a 1 so as to overlap with the data line 6 a in plan view. Anend portion of the main body portion 4 a 1 is electrically coupled tothe pixel electrode-side source drain region le of the semiconductorlayer la via a contact hole 42 a formed in the interlayer insulatinglayer 42. The first capacitance electrode 4 a is provided with a notch 4a 3 so as not to overlap in plan view with an end portion, overlappingwith the data line 6 a, of the semiconductor layer 1 a.

The second capacitance electrode 5 a includes a main body portion 5 a 1that overlaps with the main body portion 4 a 1 of the first capacitanceelectrode 4 a in plan view, and a protruding portion 5 a 2 overlappingwith the protruding portion 4 a 2 of the first capacitance electrode 4 ain plan view. Therefore, the capacitance element 55 includes a firstelement portion 551 extending in the second direction X so as to overlapwith the semiconductor layer 1 a, and a second element portion 552extending in the first direction Y so as to overlap with the data line 6a. Further, similarly to the first capacitance electrode 4 a, the secondcapacitance electrode 5 a is provided with a notch 5 a 3 so as not tooverlap with the end portion, overlapping with the data line 6 a, of thesemiconductor layer 1 a in plan view. Further, in an end portion, on thesecond side X2 in the second direction X, of the main body portion 5 a 1of the second capacitance electrode 5 a, a notch portion 5 a 4 is formedsuch that the second capacitance electrode 5 a does not overlap with theend portion of the main body portion 4 a 1 of the first capacitanceelectrode 4 a.

Returning to FIG. 5 and FIG. 6 again, the interlayer insulating layers44 and 45 are formed on the upper layer side of the interlayerinsulating layer 43. In the space between the interlayer insulatinglayer 43 and the interlayer insulating layer 44, the data line 6 a andthe relay electrodes 6 b and 6 c are provided. The data line 6 a and therelay electrodes 6 b and 6 c are formed of the same conductive film. Thedata line 6 a and the relay electrodes 6 b and 6 c are each formed of aconductive film having light shielding properties such as a metalsilicide film, a metal film, a metal compound film, or the like. Forexample, the data line 6 a and the relay electrodes 6 b and 6 c areformed by a multilayer structure of a titanium layer/a titanium nitridelayer/an aluminum layer/a titanium nitride layer, or a multilayerstructure of a titanium nitride layer/an aluminum layer/a titaniumnitride layer.

A contact hole 43 a is provided in the interlayer insulating layers 42and 43, and the contact hole 43 a penetrates through the interlayerinsulating layers 42 and 43 and the gate insulating layer 2. The dataline 6 a is electrically coupled to the data line-side source drainregion 1 t via the contact hole 43 a. The contact hole 43 a is formed ina section corresponding to the notch 4 a 3 of the first capacitanceelectrode 4 a and the notch 5 a 3 of the second capacitance electrode 5a, which are described above with reference to FIG. 8. Therefore, thecontact hole 43 a and the capacitance element 55 can be separated fromeach other. A contact hole 43 b is provided in the interlayer insulatinglayer 43, and the contact hole 43 b penetrates the interlayer insulatinglayer 43. The relay electrode 6 b is electrically coupled to the firstcapacitance electrode 4 a via the contact hole 43 b. The contact hole 43b is formed in a section corresponding to the notch 5 a 4 of the secondcapacitance electrode 5 a, which is described above with reference toFIG. 8. A contact hole 43 c is provided in the interlayer insulatinglayer 43, and the relay electrode 6 c is electrically coupled to thesecond capacitance electrode 5 a via the contact hole 43 c.

In the space between the interlayer insulating layer 44 and theinterlayer insulating layer 45, the capacitance line 7 a and the relayelectrode 7 b are provided. The capacitance line 7 a and the relayelectrode 7 b are formed of the same conductive film. The capacitanceline 7 a and the relay electrode 7 b are each formed of a conductivefilm having light shielding properties such as a metal silicide film, ametal film, a metal compound film, or the like. For example, thecapacitance line 7 a and the relay electrode 7 b are formed by themultilayer structure of a titanium layer/a titanium nitride layer/analuminum layer/a titanium nitride layer, or the multilayer structure ofa titanium nitride layer/an aluminum layer/a titanium nitride layer.

A contact hole 44 c is provided in the interlayer insulating layer 44,and the capacitance line 7 a is electrically coupled to the relayelectrode 6 c via the contact hole 44 c. Therefore, the capacitance line7 a is electrically coupled to the second capacitance electrode 5 a viathe relay electrode 6 c, and the common potential is applied to thesecond capacitance electrode 5 a from the capacitance line 7 a. Acontact hole 44 b is provided in the interlayer insulating layer 44, andthe relay electrode 7 b is electrically coupled to the relay electrode 6b via the contact hole 44 b.

A contact hole 45 a is provided in the interlayer insulating layer 45,and the pixel electrode 9 a is electrically coupled to the relayelectrode 7 b via the contact hole 45 a. Therefore, the pixel electrode9 a is electrically coupled to the first capacitance electrode 4 a viathe relay electrodes 7 b and 6 b. Here, since the first capacitanceelectrode 4 a is electrically coupled to the pixel electrode-side sourcedrain region le via the contact hole 42 a, the pixel electrode 9 a iselectrically coupled to the pixel electrode-side source drain region levia the first capacitance electrode 4 a.

4. Detailed Configuration of First Opening 41 a, Second Opening 41 b,and the Like

FIG. 10 is an enlarged plan view of the periphery of the first opening41 a and the second opening 41 b illustrated in FIG. 7. FIG. 11 is across-sectional view taken along a line C-C′ illustrated in FIG. 10. Thegate electrode 8 a is formed by layering a polysilicon layer 81 a and alight shielding layer 82 a. Note that in FIG. 10, the polysilicon layer81 a is hatched by diagonal lines sloping downward to the right, and thelight shielding layer 82 a is hatched by diagonal lines sloping upwardto the right. Therefore, a region hatched by both the diagonal linessloping downward to the right and the diagonal lines sloping upward tothe right indicates that both the polysilicon layer 81 a and the lightshielding layer 82 a are layered in the region.

As illustrated in FIG. 10 and FIG. 11, the first opening 41 a and thesecond opening 41 b extend along the second direction X on both sides ofthe semiconductor layer 1 a. The first opening 41 a and the secondopening 41 b are both provided at positions overlapping with the gateelectrode 8 a in plan view. Therefore, a portion of the gate electrode 8a is disposed inside each of the first opening 41 a and the secondopening 41 b. Thus, the gate electrode 8 a configures a light shieldingwall inside each of the first opening 41 a and the second opening 41 b.

The first opening 41 a and the second opening 41 b are provided at leastalong the pixel electrode-side LDD region lf. In the present exemplaryembodiment, the first opening 41 a and the second opening 41 b at leastextend from both sides of the data line-side LDD region lu to both sidesof the pixel electrode-side LDD region lf, via both sides of the channelregion 1 c.

The gate electrode 8 a is configured by layering the conductivepolysilicon layer 81 a that extends in the first direction Y so as tointersect with the semiconductor layer 1 a, and the light shieldinglayer 82 a covering the polysilicon layer 81 a. The light shieldinglayer 82 a is formed from a material having higher light shieldingproperties than the polysilicon layer 81 a. For example, the lightshielding layer 82 a is formed of a light shielding film such as atungsten silicide.

The light shielding layer 82 a is formed over a wider area than thepolysilicon layer 81 a and covers the entire polysilicon layer 81 a.Therefore, in a region of the gate electrode 8 a in which thepolysilicon layer 81 a is formed, the polysilicon layer 81 a and thelight shielding layer 82 a are provided forming a two-layer structure,and in a region of the gate electrode 8 a in which the polysilicon layer81 a is not formed, only the light shielding layer 82 a is providedforming a single-layer structure. For example, in the gate electrode 8a, the polysilicon layer 81 a is not formed inside the first opening 41a and the second opening 41 b, and thus the interior of the firstopening 41 a and the second opening 41 b has the single-layer structureconfigured by the light shielding layer 82 a. Therefore, the lightshielding layer 82 a is provided along the entire inner wall of each ofthe first opening 41 a and the second opening 41 b. On the other hand,of the first electrode portion 8 a 0 that extends in the first directionY in the gate electrode 8 a, a portion outside the first opening 41 aand the second opening 41 b has the two-layer structure configured bythe polysilicon layer 81 a and the light shielding layer 82 a. Note thatportions provided on both sides in the extending direction of the firstopening 41 a and the second opening 41 b have the single-layer structureconfigured by the light shielding layer 82 a.

In the first opening 41 a and the second opening 41 b configured in thismanner, the first opening 41 a formed on one side, of both the sides, ofthe semiconductor layer 1 a overlaps with the scanning line 3 a in planview, and the gate electrode 8 a is in contact with the semiconductorlayer 1 a side of the scanning line 3 a via the first opening 41 a.Therefore, the first opening 41 a is configured as the contact hole 41 gthat electrically couples the gate electrode 8 a with the scanning line3 a. Thus, a scanning signal is applied to the gate electrode 8 a fromthe scanning line 3 a.

On the other hand, the second opening 41 b does not overlap with thescanning line 3 a in plan view. Thus, the gate electrode 8 a is not incontact with the scanning line 3 a via the second opening 41 b and is incontact with the substrate main body 19. In order to achieve such aconfiguration, in the present exemplary embodiment, the semiconductorlayer 1 a is provided at a position biased from the center of thescanning line 3 a in the width direction toward the second side Y2,namely the other side of the scanning line 3 a, in the first directionY. In other words, the semiconductor layer 1 a is provided at a positionbiased from the center of the scanning line 3 a toward the secondopening 41 b side in the width direction. Thus, a distance between thesemiconductor layer 1 a and the second opening 41 b and a distancebetween the semiconductor layer 1 a and the first opening 41 a are thesame. Therefore, the gate electrode 8 a provided inside the secondopening 41 b and the gate electrode 8 a provided inside the firstopening 41 a have similar light shielding properties with respect to thesemiconductor layer 1 a.

5. Method for Manufacturing Electro-optical Device 100

FIG. 12 is an explanatory diagram illustrating a method formanufacturing the electro-optical device 100 illustrated in FIG. 1, andis an explanatory diagram illustrating steps for forming the gateelectrode 8 a. When manufacturing the gate electrode 8 a illustrated inFIG. 10 and FIG. 11, after forming the scanning line 3 a, the interlayerinsulating layer 41, the semiconductor layer 1 a, and the gateinsulating layer 2, at step ST1 illustrated in FIG. 12, a conductivepolysilicon film is formed, and then, the polysilicon film is patternedto form the polysilicon layer 81 a that extends in the first direction Yintersecting the semiconductor layer 1 a.

Next, at step ST2 illustrated in FIG. 12, in a state in which an etchingmask is formed, the polysilicon layer 81 a and the interlayer insulatinglayer 41 are etched to form the first opening 41 a and the secondopening 41 b. Therefore, the polysilicon layer 81 a is not presentinside the first opening 41 a and the second opening 41 b. Further, whenforming the first opening 41 a and the second opening 41 b, the scanningline 3 a functions as an etching stopper.

Next, after forming a light shielding film, the light shielding film ispatterned to form the light shielding layer 82 a, as illustrated in FIG.10.

6. Main Effects of Present Exemplary Embodiment

As described above, in the electro-optical device 100 according to thepresent exemplary embodiment, light incident from the second substrate20 side is blocked by the wiring lines, such as the data lines 6 a andthe capacitance lines 7 a provided on the second substrate 20 side withrespect to the semiconductor layer 1 a, and the capacitance element 55.Thus, incidence of the light on the semiconductor layer 1 a issuppressed. Further, even when light emitted from the first substrate 10side enters once again from the first substrate 10 side, the light isblocked by the scanning lines 3 a provided on the substrate main body 19side with respect to the semiconductor layer 1 a, so incidence of thelight on the semiconductor layer 1 a is suppressed.

Further, with respect to light traveling in the first direction Yintersecting the semiconductor layer 1 a, since the gate electrode 8 aconfigures a light shielding wall inside each of the first opening 41 aand the second opening 41 b, the incidence of light on the semiconductorlayer 1 a is suppressed. In particular, in the present exemplaryembodiment, by providing the pixel electrode-side LDD region if betweenthe channel region 1 c and the pixel electrode-side source drain region1 e, an off-leak current of the transistor 30 is reduced, and at thesame time, the light shielding wall is configured by the gate electrode8 a provided inside each of the first opening 41 a and the secondopening 41 b. Therefore, light traveling toward the pixel electrode-sideLDD region if can be efficiently blocked, and the transistor 30 can thussufficiently exhibit characteristics of the LDD structure.

Further, in the present exemplary embodiment, of the first opening 41 aand the second opening 41 b provided on both sides of the semiconductorlayer 1 a, only the first opening 41 a overlaps with the scanning line 3a in plan view, and the second opening 41 b does not overlap with thescanning line 3 a in plan view. Thus, the width of the scanning line 3 acan be made narrower compared with a case in which both the firstopening 41 a and the second opening 41 b are disposed so as to overlapwith the scanning line 3 a in plan view. For example, as in the presentexemplary embodiment, the width of the scanning line 3 a can be madenarrower than the width of the data line 6 a. Thus, a reduction in apixel aperture ratio, which is a proportion of the aperture regions 11illustrated in FIG. 3, can be avoided, and thus, utilization efficiencyof light can be increased.

Further, the gate electrode 8 a includes the conductive polysiliconlayer 81 a and the light shielding layer 82 a, and the light shieldinglayer 82 a is provided along the inner wall of each of the first opening41 a and the second opening 41 b. Thus, a high light shieldingperformance is obtained in the first opening 41 a and the second opening41 b.

Second Exemplary Embodiment

FIG. 13 is an explanatory diagram illustrating the electro-opticaldevice according to a second exemplary embodiment of the presentdisclosure. FIG. 13 illustrates an enlarged cross-section of theperiphery of the second contact hole 41 g, which corresponds to thecross section taken along the line C-C′ illustrated in FIG. 4. Note thatbasic configurations in this exemplary embodiment are the same as thoseof the first exemplary embodiment, and thus, common portions will bedenoted by the same reference signs and a description of the commonportions will be omitted.

As illustrated in FIG. 13, in the electro-optical device according tothe present exemplary embodiment, similarly to the first exemplaryembodiment, the first opening 41 a overlaps with the scanning line 3 ain plan view, and the second opening 41 b does not overlap with thescanning line 3 a in plan view. In the present exemplary embodiment,only a portion of the first opening 41 a overlaps with the scanning line3 a in plan view. Therefore, the gate electrode 8 a is in contact withthe surface 3 a 5, on the semiconductor layer 1 a side, of the scanningline 3 a and a side surface 3 a 6 of the scanning line 3 a. According tosuch a configuration, while using the scanning line 3 a as an etchingstopper, the first opening 41 a is formed to a deep position. Thus, thescanning line 3 a can be reliably exposed at the bottom of the firstopening 41 a. Therefore, the gate electrode 8 a can be reliablyelectrically coupled to the scanning line 3 a via the first opening 41a.

Third Exemplary Embodiment

FIG. 14 is an explanatory diagram illustrating the electro-opticaldevice according to a third exemplary embodiment of the presentdisclosure. FIG. 14 illustrates an enlarged cross section of theperiphery of the second contact hole 41 g, which corresponds to thecross section taken along the line C-C′ illustrated in FIG. 4. Note thatbasic configurations in this exemplary embodiment are the same as thoseof the first exemplary embodiment, and thus, common portions will bedenoted by the same reference signs and a description of the commonportions will be omitted.

As illustrated in FIG. 14, in the electro-optical device according tothe present exemplary embodiment, similarly to the first exemplaryembodiment, the first opening 41 a overlaps with the scanning line 3 ain plan view, and the second opening 41 b does not overlap with thescanning line 3 a in plan view. In the present exemplary embodiment, thesecond opening 41 b is provided to a position deeper than a surface ofthe scanning line 3 a on the opposite side from the semiconductor layer1 a. More specifically, the second opening 41 b penetrates theinterlayer insulating layer 41, and reaches the substrate main body 19.Therefore, in the substrate main body 19, a hole 19 a, which is formedwhen forming the second opening 41 b by etching, is formed at a positionoverlapping with the second opening 41 b. According to such aconfiguration, while using the scanning line 3 a as an etching stopper,the first opening 41 a and the second opening 41 b are each formed to adeep position. Thus, the scanning line 3 a can be reliably exposed atthe bottom of the first opening 41 a. Therefore, the gate electrode 8 acan be reliably electrically coupled to the scanning line 3 a via thefirst opening 41 a. Such a configuration may be applied to theelectro-optical device according to the third exemplary embodiment.

Other Exemplary Embodiments

In the first, second, and third exemplary embodiments described above,the semiconductor layer 1 a extends in the second direction X along thescanning line 3 a, but the present disclosure may be applied to theelectro-optical device 100 in which the semiconductor layer 1 a extendsin the first direction Y along the data line 6 a, or to theelectro-optical device 100 in which the semiconductor layer 1 a is bentso as to extend along the data line 6 a and the scanning line 3 a.

Example of Installation in Electronic Apparatus

An electronic apparatus using the electro-optical device 100 accordingto the above-described exemplary embodiments will be described below.FIG. 15 is a schematic configuration view of a projection-type displayapparatus using the electro-optical device 100 to which the presentdisclosure is applied. An illustration of optical elements, such as apolarizing plate, is omitted in FIG. 15. A projection-type displayapparatus 2100 illustrated in FIG. 15 is an example of the electronicapparatus using the electro-optical device 100. The projection-typedisplay device 2100, in which the electro-optical device 100 is used asa light valve, can perform high-definition and bright display withoutmaking the apparatus large. As illustrated in FIG. 17, a light sourceunit 2102 including a white light source, such as a halogen lamp, andthe like is provided inside the projection-type display apparatus 2100.Projection light emitted from the light source unit 2102 is split intothree primary colors of R (red), G (green), and B (blue) by threemirrors 2106 and two dichroic mirrors 2108 installed inside. The splitincident light is guided to light valves 100R, 100G, and 100Bcorresponding to each of the primary colors, and then modulated. Notethat since the light of the B color has a long optical path compared tothe other light of the R color and the G color, the light of the B coloris guided via a relay lens system 2121 including an incidence lens 2122,a relay lens 2123, and an emission lens 2124, to prevent loss due to thelong optical path of the light of the B color.

The light modulated by each of the light valves 100R, 100G, and 100B isincident on a dichroic prism 2112 from three directions. Then, at thedichroic prism 2112, the light of the R color and the light of the Bcolor are reflected at 90 degrees, and the light of the G color istransmitted. Therefore, after images of each of the primary colors aresynthesized, a color image is projected onto a screen 2120 by aprojection optical system 2114.

Other Projection-Type Display Apparatuses

Note that the projection-type display apparatus may include aconfiguration in which an LED light source or the like configured toemit light of each color is used as a light source unit and the light ofeach color emitted from the LED light source is supplied to anotherliquid-crystal device.

Other Electronic Apparatuses

The electronic apparatus including the electro-optical device 100 towhich the present disclosure is applied is not limited to theprojection-type display device 2100 of the above-described exemplaryembodiment. Examples of the electronic apparatus may include aprojection-type head up display, a direct-view-type head mounteddisplay, a personal computer, a digital still camera, and a liquidcrystal television.

What is claimed is:
 1. An electro-optical device comprising: a scanningline; a transistor including a semiconductor layer extending in anoverlapping manner with the scanning line in plan view and a gateelectrode having light shielding properties and disposed on a side,opposite from the scanning line, of the semiconductor layer; and aninterlayer insulating layer disposed in a layer between the transistorand the scanning line, the interlayer insulating layer including a firstopening and a second opening provided with the semiconductor layerinterposed therebetween in plan view, a portion of the gate electrodebeing provided inside the first opening and the second opening, whereinthe first opening is provided at a position overlapping with thescanning line in plan view, and the second opening is provided at aposition not overlapping with the scanning line in plan view.
 2. Theelectro-optical device according to claim 1, comprising: a pixelelectrode provided corresponding to the transistor, wherein thesemiconductor layer includes a channel region overlapping with the gateelectrode in plan view, a pixel electrode-side source drain regionelectrically connected to the pixel electrode, and a pixelelectrode-side LDD region interposed between the channel region and thepixel electrode-side source drain region in plan view, and the firstopening and the second opening are provided at least along the pixelelectrode-side LDD region.
 3. The electro-optical device according toclaim 1, wherein the semiconductor layer extends along the scanningline.
 4. The electro-optical device according to claim 3, wherein thesemiconductor layer is provided at a position on the second opening sideof a center, in a width direction, of the scanning line.
 5. Theelectro-optical device according to claim 3, comprising: a data lineextending in a direction intersecting the scanning line, wherein a widthof the scanning line is narrower than a width of the data line.
 6. Theelectro-optical device according to claim 1, wherein the gate electrodeincludes a conductive polysilicon layer, and a light shielding layerhaving higher light shielding properties than the polysilicon layer, andthe light shielding layer is provided along an inner wall of each of thefirst opening and the second opening.
 7. The electro-optical deviceaccording to claim 1, wherein the gate electrode is in contact, via thefirst opening, with a surface of the scanning line on a side of thesemiconductor layer, and with a side surface of the scanning line. 8.The electro-optical device according to claim 1, wherein the secondopening is provided up to a position on an opposite side of the scanningline from a side of the semiconductor layer.
 9. An electronic apparatuscomprising: the electro-optical device according to claim 1.